On demand electronic faucet

ABSTRACT

An on-demand electronic faucet system for providing a faucet with a flow of water in response to a stimulus. A sensor unit is positioned remote from the faucet and in wireless communication with a wireless valve control unit. The wireless valve control unit controls a valve in the water supply line that feeds the faucet. In response to a stimulus, the sensor signals the wireless valve control unit to change the status of the valve in the water supply line from open to closed or closed to open and other states affecting flow and temperature.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This application is a reissue of U.S. Pat. No. 7,979,928 (previouslyU.S. patent application Ser. No. 11/863,191, filed Sep. 27, 2007, whichclaims priority from U.S. Provisional Patent Application No. 60/848,430,filed Sep. 29, 2006, herein incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

The present invention relates generally to the field of faucets. Moreparticularly the present invention relates to the field of automaticon-demand electronic faucets.

Recent trends in bathroom design have begun to stress the importance ofusing “hands-free” electronic faucets. Hands-free electronic faucets arefaucets that do not require the typical physical manipulation of a leveror handle to activate the flow of water. Numerous electronic faucetsystems have been developed to accomplish this using various detectionsystems such as infrared, RF (radio frequency), capacitance, optical,and audio. Hands-free systems thus allow users to operate the faucetwithout the need to touch the hot/cold on/off knobs.

This hands-free feature for water control provides several desirablefeatures. First, a hands-free system provides improved hygienicproperties as a user is not required to physically touch any part of thefaucet or basin. This is particularly important in high-trafficlocations, such as in the commercial setting. This advantage is alsodesirable in the residential setting in reducing clean-up and preventingthe spread of bacteria.

A second feature of hands-free systems is their ease of use. Often auser would find activation of a traditional faucet knob difficult, i.e.when their hands are slick due to soap or the hands are heavily soiled.Hands-free systems allow a user to simply trigger the sensor to startthe flow of water. However, many conventional on-demand systems requirea user to place their hands under the faucet to trigger water flow. Thisarrangement can limit how a user is able to use the device.

A third benefit of on-demand systems is water conservation. Allhands-free faucets include an automatic shut-off feature, which may bebased on a timer mechanism. Such a feature conserves water and a useralso does not need to worry about turning the faucet off. Typicallyon-demand systems use less water than traditional manual systems, inlarge part because of user's failure to turn the manual systems off. Insome automatic systems, the water only comes on when the user's handsare directly below the water exit point. Thus, the ability toincorporate an automatic off-feature allows for more efficient use ofwater than is typically experienced with traditional faucets.

Although hands-free systems provide numerous benefits, current systemsalso fail to provide a user with several desired types of functionality.First, with few exceptions, current electronic systems do not allow auser to control, without manual adjustments, the flow of hot and coldwater separately or the temperature of the blended stream which exitsthe faucet. This can be a particular concern for faucets where coldwater for drinking, mild water for hand-washing, and hot water for roomcleaning may all be required from the same faucet.

Second, an additional constraint that current systems have is their needfor a specific fixed activation zone. Regardless of the type of sensorsystem used, i.e. infrared, RF, capacitance, RF, etc, the hands-freesystem will have a certain zone of detection where a “target” needs toenter in order to activate the faucet. Current systems typically includea sensor in a fixed position in the faucet or basin, requiring a user'shands to be placed into the basin detection zone to activate the flow ofwater. While this may be acceptable for simple hand washing, such adesign is ineffective for other applications proximate the sink.

Third, current hands-free systems restrict the aesthetic design of thefaucet due to the requirement of a sensor in the faucet as previouslydiscussed. This results in users having less variety of faucets tochoose from, which may be of particular concern in residentialapplications.

Fourth, current systems do not provide for retro-fitting of traditionalfaucets. Typically, users must undertake the expense of an entire newfaucet to enjoy the benefits of hands-free functionality, since thesensor is fixed in the basin of the faucet.

SUMMARY OF THE INVENTION

One embodiment of the invention relates to an on-demand electronicsystem. The system comprises a sensor unit. The sensor unit includes ahousing with a sensor for detecting at least one stimulus and a wirelesscommunication device, the sensor unit being located remote from thefaucet. The on-demand electronic system also includes at least onewireless control valve device comprising a second wireless communicationdevice in operative communication with a water feed valve and inwireless communication with the sensor wireless communication device.Upon detection of a plurality of stimuli, a signal is transmitted fromthe sensor unit to the wireless control valve device, thereby triggeringa change in the state of the valve, such as turning the water on or off.

In one exemplary embodiment, a wireless electronic control valve ispositioned on both the hot and cold water supply lines and both wirelesselectronic control valves are in communication with the sensor unit. Thesensor unit is capable of detecting and distinguishing between at leasttwo stimuli, where a first signal is sent to the hot water valve inresponse to a first stimulus and a second signal is sent to the coldwater valve in response to a second stimulus.

These and other objects, advantages, and features of the invention,together with the organization and manner of operation thereof, willbecome apparent from the following detailed description when taken inconjunction with the accompanying drawings, wherein like elements havelike numerals throughout the several drawings described below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a perspective view of a conventional manual faucet withseparate hot and cold handles and two single control valves; FIG. 1B isa perspective view of conventional manual faucet with a singletemperature and flow handle and a dual-control valve;

FIG. 2 is a perspective view of an on-demand faucet system with twosingle-control valves;

FIG. 3 is a perspective view of an on-demand faucet system with adual-control valve;

FIG. 4 is an illustration of a sensor unit of the present invention;

FIG. 5 is another exemplary embodiment of a sensor unit of the presentinvention having a light source;

FIG. 6A is an exemplary embodiment of the system of FIG. 2 having atemperature sensor; and 6B is another exemplary embodiment of a sensorunit of the present invention having a display for indicating watertemperature; and

FIG. 7 is another exemplary embodiment of a sensor unit of the presentinvention having a manual actuation mechanism.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

As shown in FIGS. 1A and 1B, traditional faucet systems include a faucet10, a vanity 11, a basin 12, a hot water supply line 14, and a coldwater supply line 16. Some prior art systems (FIG. 1A) utilize separatehot and cold water supply lines 14, 16 each controlled respectively by ahot water handle 18, and a cold water handle 20 with the aggregate waterflow through both supply lines 14, 16 determining the temperature of thewater flowing from the faucet 10. Other prior art systems utilize asingle handle 17 (see FIG. 1B) that functions to control both the hotand cold water flow. Such prior art faucet systems include a fixedposition sensor 13 embedded in the faucet 10, or in the basin 12 itself,such that presence of an object in a portion of the basin 12 may bedetected.

The present invention relates to a hands-free faucet system havingon-demand functionality. As shown in FIG. 2 and FIG. 3, the on-demandsystem 100 includes a sensor unit 22 (shown in greater detail in FIG. 4)in communication with at least one wireless valve control unit 21 forthe control of the flow of water from the water lines 14 and 16 to thefaucet 10. In one embodiment, the flow of water is regulated by means ofat least one valve 23 controlled by the at least one wireless valvecontrol unit 21.

In one exemplary embodiment illustrated in FIG. 3, the at least onewireless valve control unit 21 comprises a wireless hot water valvecontrol unit 24 and a wireless cold water valve control unit 26. The atleast one valve 23 comprises a hot water valve 25 and a cold water valve27. The wireless hot water valve control unit 24 is in communicationwith the hot water valve 25; and the wireless cold water valve controlunit 26 is in communication with the cold water valve 27 such that theunits 24 and 26 control the hot water line 14 and the cold water line16, respectively. Thus, each of the water lines 14 and 16 areeffectively in communication with the sensor unit 22 such that theirrespective flows can be turned on and off as a result of a signal fromthe sensor unit 22.

In the embodiment illustrated in FIG. 2, the wireless valve control unit21 is a single unit in communication with a single valve unit 23. Thesingle valve unit 23 may comprise a two-control valve such as, but notlimited to, the type described in U.S. Pat. No. 6,508,272, which isincorporated herein by reference. Thus, the flow of both the hot waterline 14 and the cold water line 16 may be controlled via a singlewireless valve control unit 21.

The sensor unit 22 is separate from the faucet 10, allowing it to bepositioned as needed by a user. FIG. 4, illustrates one exemplaryembodiment of the sensor unit 22. In one embodiment the sensor device isremovably fixable to a surface, such as but not limited to the vanity 11shown in FIG. 3. The sensor unit need only be placed so as to be inwireless communication with the hot and cold control valves units 24, 26respectively.

The sensor unit 22 includes a housing 39, a power source such as abattery (not shown) and a sensor 34 which is capable of detecting a userindicated trigger. In an exemplary embodiment, the electronic componentsmay be part of a printed circuit board (not shown). The sensor 34 has azone of detection 40, in which it is capable of detecting one or morestimuli (such as presence of a user's hands). In one embodiment, thesensor 34 is a passive infrared (PIR) detector which are well known inthe art. Generally, in order to detect a human being, PIR detectors mustbe sensitive to the temperature difference of a human body compared tothe surrounding. Humans, having a skin temperature of about 93 degreesF., radiate infrared energy with a wavelength between 9 and 10micrometers. In an exemplary embodiment, the sensor unit 22 is sensitiveto infrared energy having wavelengths in the range of about 8 to about12 micrometers. While the present invention has been described inrelation to PIR, the use of various conventional detection technologiesis within the scope of the present invention. Such conventionaldetection technologies include but are not limited to: active infra-red,capacitance detection, passive optical detection (e.g., a photo cell),thermal detection such as passive infrared or thermopiles, RF. In oneembodiment, because the zone of detection is tied to the location of thesensor unit 22 and the sensor unit 22 may be movable, the zone ofdetection 40 is not fixed in relation to the faucet 10, but can beadjusted by moving the sensor unit 22.

The sensor unit 22 includes a sensor unit wireless communication device30 (see FIGS. 4 and 5) for communicating with at least one valve controlunit wireless communication device 31 associated with the wireless valvecontrol units 24, 26 (element 30 is depicted as an antennae forgraphical clarity. The actual device may not be external and indeed maybe within the housing). In an exemplary embodiment, the wirelesscommunication device 30 comprises a radio frequency (“RF”) transmitterwith the valve control unit wireless communication device 31 including acorresponding RF receiver. The sensor unit 22 transmits an RF signalwhen the sensor 34 detects a stimulus.

In one embodiment shown in FIG. 4, the sensor unit wirelesscommunication device 30 comprises a sensor unit transceiver, and thevalve control unit wireless communication device 31 comprises at leastone valve control unit transceiver. The transceivers provide forsend/receive communications capabilities. The use of a transceiverallows one to guarantee signal integrity (i.e. when data is sent it canbe verified by sensor unit 22 that the wireless control valve unit 21received the correct data by asking the receiver to send back averification). In one embodiment, the verification is done via achecksum. If the checksum is correct, the data received by thetransmitter was correctly received.

In an exemplary embodiment, the present invention contemplates the useof multiple RF communication devices. In one embodiment, each RFtransmission is encoded with a digital ID tag or bit. The receiverswithin RF range listen to the RF communication, but unless the ID iscorrect, no action will be taken. In one embodiment, the sensor unitwireless communication device 30 and the valve control unit wirelesscommunication device 31 are a paired unit with the same ID so that whenthe sensor unit 22 transmits, the appropriate wireless control valveunit 24, 26 will respond. In another embodiment, the sensor unitwireless communication device 30 and the valve control unit wirelesscommunication device 31 use the same frequency transmissions, whereinonly matched frequency paired units will respond to one another. Thatis, the sensor unit 22 and wireless valve control unit 21 are tuned tothe same frequency.

In one exemplary embodiment, the sensor unit 22 is adapted to detectvarious stimuli. In one embodiment the sensor unit 22 detects anddifferentiates a right to left hand motion of a user from a left toright hand motion within the zone of detection 40. In one embodiment, afirst right to left hand motion results in a particular type of signalfrom the sensor unit 22 which is received by the wireless hot watervalve control unit 24. In response to the first right to left handmotion, the hot water valve 25 reverses its state, i.e. it opens if itwas closed and closes if it was opened. In an exemplary embodiment, thewireless cold water valve control unit 26 operates in the same manner inresponse to a left to right hand motion. While the sensor unit 22 hasbeen described as detecting a left to right hand motion versus a rightto left hand motion, one of ordinary skill in the art will appreciatethat various types of motions and number of preparation for control ofwater flow rate and temperature are understood to be within the spiritof the invention.

By responding to a signal by reversing state, the present inventionallows for a user to both turn the water flow on and off. For example,in one embodiment, a user approaches the faucet 10 (with the flow ofwater closed) and motions with a hand right to left through the zone ofdetection 40. This signals the wireless hot water valve control unit 24,which switches the hot water valve 25 (i.e. from off to on assuming thevalve was closed), allowing the user to wash their hands. A timer (notshown) is initiated, which will trigger the hot water valve 25 to closeafter a predetermined amount of time if a user does not initiate anothersignal. When the user finishes, they provide a hand motion right to leftagain through the zone of detection 40 resulting in a second signal tothe hot water valve 25 stopping the flow of hot water. Thus, a user isprovided with a hands-free option away from the faucet 10 to shut thewater flow off, a feature absence from current hands-free systems andwhich allows for even more rigorous control of water usage than relianceon a timer based automatic shutoff alone.

In one exemplary embodiment, the present invention provides for handsfree variable control of the water flow volume. In one embodiment, thesensor unit 22, in response to a certain stimulus or stimuli, transmitsto the wireless control valve unit 21 a signal to the amount theselected valve is opened providing for variable flows beyond the simpleon and off state. In an exemplary embodiment, the hot water valve 25 andthe cold water valve 27 are both independently variably controlled bythe wireless valve control unit 21 allowing for a myriad of flowcombinations resulting in potential temperatures ranging from hot tocold.

In one exemplary embodiment, the faucet 10 includes at least one manualcontrol (i.e. handle). A traditional two handle embodiment is shown inFIG. 1, having the hot water handle 18 and the cold water handle 20 forcontrolling the hot and cold water respectively. In one embodiment, auser may set the handles 18, 20 for desired flow and/or mixture of hotand cold water. When the on-demand system 100 (see FIG. 2) is activatedto allow water flow, the water will flow from the faucet 10 inaccordance with the setting of the handles 18, 20. In another exemplaryembodiment, the faucet 10 does not include traditional handles forcontrolling the flow of water. In one embodiment, manual control valves68, 69 are placed on the hot water line 14 and the cold water line 16respectively to allow a user to manually set the flow of water and thetemperature of water (i.e. the relative ratio of hot to cold water)available to the faucet 10 when the on-demand system 100 is activated.

In one exemplary embodiment, the sensor unit 22 sends a signal to thewireless valve control unit 21, which in turn controls the valves 25, 27(or 23 in the embodiment of FIG. 2) that is indicative of certainparameters. For example, a user may provide a certain stimulus whichcorresponds to a change in the flow of water providing the user with theoption of a variable flow. Upon detection of a predetermined stimulus,the sensor unit 22 transmits a signal to the wireless valve control unit21 indicating a change in water flow. The wireless valve control unit 21then adjusts the valve unit 23 as appropriate. Thus a user can utilizeparticular stimuli to variably control the water flow.

In one embodiment shown in FIG. 6A, the present invention allows for notonly control of flow, but of temperature. In an exemplary embodiment, inresponse to a first stimulus, the sensor unit 22 sends a first signal tothe hot water valve control unit 25 which alters the state of the hotwater valve 25 without regard to the state of the cold water valve 27.In response to a second stimulus, the sensor unit 22 sends a secondsignal to the wireless cold water valve control unit 26 which alters thestate of the cold water valve 27 without regard to the state of the hotwater valve 25.

In one embodiment, illustrated in FIG. 5, a visible light source 44 canbe integrated into the sensor unit 22. In an exemplary embodiment, thelight source 44 is in communication with a light sensor 46 whereby thelight source 44 is on when low or no light levels are detected. Thus,the sensor unit 22 can also have the functionality of a nightlight orbecause for identifying its operative location. In an exemplaryembodiment, the area lit by the light source 44 substantiallycorresponds to the zone of detection 40. In another exemplaryembodiment, the area lit by the light source 44 roughly corresponds tothe location of or actual geometry for the basin 12 for the faucet 10.This night light feature can also provide useful positional and obstacleinformation at night time, such as the location of a vanity, basin, orfaucet while generally illuminating the area.

In another embodiment, illustrated in FIGS. 6A and 6B, the wirelesscontrol valve unit 21 include a temperature sensor (not shown) typicallylocated on the water supply that measures the mixed water temperature.In an exemplary embodiment, the sensor unit 22 includes a display 50(FIG. 6B) in communication with the temperature sensor (not shown) fordisplaying the temperature. In another exemplary embodiment thetemperatures sensor 48 is provided downstream from the wireless controlvalve unit 21 and is in communication with the sensor unit 22. Inanother exemplary embodiment, an emergency cutoff mechanism is providedwhereby the flow of liquid to the faucet 10 is interrupted if thetemperature of the liquid exceeds a certain threshold.

In one embodiment, illustrated in FIG. 4, the sensor unit 22 furtherincludes manual buttons 60 for activation of the valves 25, 27 (FIG.6A). In an exemplary embodiment, at least one button 60 is provided.Actuation of the button 60 results in a signal from the sensor unitwireless communication device 30 of the sensor unit 22 to the valvecontrol unit wireless communication device 31 of the wireless controlvalve unit 21 (FIG. 2). In one embodiment (FIG. 7), a single button 60provided which regulates the flow of water. In another embodiment (FIG.7), a pair of buttons 61, 62 are provided, with a cold water manualcontrol button 61 corresponding to flow of cold water and a hot watermanual control button 61 corresponding to the flow of hot water. In anexemplary embodiment, a user activates the button 62, the flow of coldwater begins and when activated again, the flow ceases. Likewise thebutton 61 controls the flow of hot water. Activation of the both buttons61 and 62 provides for tepid water. In one embodiment, the buttons 60,61, 62 provide for variable control of the water such that holding downthe button provides for a greater volume of water flow.

In one embodiment, the present invention relates to a sensor incommunication with a flow-through valve which controls temperature, butdoes not control of flow or flow volume. The wireless control valve unit21 is in operative communication with the flow-through valve to providefor control of the temperature of the water in response to a signal fromthe sensor unit 22.

In one embodiment, the sensor unit 21 may be powered by batteries. In analternative embodiment, the sensor unit 21 is receives power via astandard wall outlet, such as through the use of step down voltageadaptor transformer.

In one embodiment, an automatic shut-off timer (not shown) is provided.The automatic shutoff timer is activated when the control valve deviceis switched from closed to open, triggering a counter. A predeterminedtime value is compared to the counter value and when the predeterminedtime is exceeded the state of the control valve is changed from open toclosed if control valve does not close prior to the predetermined time.

The foregoing description of embodiments of the present invention havebeen presented for purposes of illustration and description. It is notintended to be exhaustive or to limit the present invention to theprecise form disclosed, and modifications and variations are possible inlight of the above teachings or may be acquired from practice of thepresent invention. The embodiments were chosen and described in order toexplain the principles of the present invention and its practicalapplication to enable one skilled in the art to utilize the presentinvention in various embodiments, and with various modifications, as aresuited to the particular use contemplated.

What is claimed is:
 1. A wireless apparatus for controlling water flowto a faucet fed by a water line having a hot water supply valve and acold water supply valve, the wireless apparatus comprising: a sensorunit having a housing with a sensor for detecting and differentiating aplurality of stimuli, having a manual actuation switch, and a sensorwireless communication device, the sensor unit housing located remotefrom the faucet; a wireless hot water control valve device in operativecommunication with the hot water valve such that the wireless hot watercontrol valve device selectively controls the volume of hot watersupplied to the water supply line; a wireless cold water control valvedevice in operative communication with the cold water valve such thatthe wireless cold water control valve device selectively controls thevolume of cold water supplied to the water supply line wherein upondetection of a first stimulus of the plurality of stimuli or actuationof the from the manual actuation switch, a first signal is transmittedfrom the sensor wireless communication device to the wireless cold watercontrol valve device thereby triggering a change in the state of thecold water supply valve and upon detection of a second stimulus of theplurality of stimuli from the manual actuation switch, a second signalis transmitted from the sensor wireless communication device to thewireless hot water control valve device thereby triggering a change inthe state of the hot water supply valve, wherein the rate of flow ofwater from the faucet is altered upon detection of a third stimulus fromthe manual actuation switch, wherein the faucet is positioned on avanity and the sensor unit housing is positioned remotely therefrom onanother portion of the vanity, the sensor unit have a zone of detectionabove the vanity, and wherein the sensor unit wireless communicationdevice transmission have has an identification code and the wirelesscold water control valve device and the wireless hot water control valvedevice respond only to transmission bearing the identification code. 2.The wireless apparatus of claim 1, wherein the sensor wirelesscommunication device comprises a sensor transceiver, the wireless coldwater control valve device also comprises a wireless cold water controlvalve transceiver, and the wireless hot water control valve device alsocomprises a wireless hot water control valve transceiver, thetransceivers being in wireless send/receive communication with eachother.
 3. The wireless apparatus of claim 2 wherein the sensortransceiver, upon transmitting data, verifies that the control valvetransceiver received the data.
 4. The wireless apparatus of claim 1,wherein the sensor unit wireless communication device and the wirelesscold water control valve device and the wireless hot water control valvedevice have paired frequencies for wireless communication.
 5. Thewireless apparatus of claim 1, wherein the sensor unit wirelesscommunication device comprises a transmitter the wireless cold watercontrol valve device comprises a receiver, and the wireless hot watercontrol valve device comprises a receiver, the transmitter and receiversin wireless communication.
 6. The wireless apparatus of claim 5, whereinthe transmitter and receivers communication via radio frequencytransmissions.
 7. The wireless apparatus of claim 1 further comprising alight positioned in the sensor unit housing.
 8. An on-demand faucetsystem comprising: a vanity having a basin and a faucet, the faucet influid communication with a water supply line formed from a hot watersupply line and a cold water supply line; a hot water valve operativelypositioned on the hot water supply line for controlling the volume ofhot water supplied to the water supply line; a wireless hot water valvereceiver in operative communication with the hot water valve such thatthe wireless hot water valve receiver selectively controls the volume ofhot water supplied to the water supply line; a cold water valveoperatively positioned on the cold water supply line for controlling thevolume of cold water supplied to the water supply line; a wireless coldwater valve receiver in operative communication with the cold watervalve such that the wireless cold water valve receiver selectivelycontrols the volume of cold water supplied to the water supply line; anda sensor unit positioned on the vanity remote from the faucet andcomprising a housing with a wireless transmitter, a manual actuationswitch, a temperature display configured to indicate the temperature ofwater at the faucet, and a sensor having a zone of detection above thevanity for presence detection, the transmitter of the sensor unit inwireless communication with the wireless hot water valve receiver andthe wireless cold water valve receiver; and wherein upon presencedetection, the flow of water supplied from the cold water supply lineand the hot water supply line to the water supply line is altered,adjusting the temperature of the water from the faucet, wherein thesensor is able to discern at least a first, second and third type ofpresence, wherein upon detection of the first type of presence, a firsttransmission is made to the hot water valve device triggering a changein state of the hot water valve and upon detection of a second type ofpresence, a second signal is transmitted to the cold water valve devicetriggering a change in state of the cold water valve, thus allowing forindependent control of the hot water supply line and the cold watersupply line, wherein the rate of flow of water from the faucet isaltered upon detection of a third type of presence, wherein the faucetis positioned on a vanity and the sensor unit is positioned remotelytherefrom on another portion of the vanity, and wherein the sensor unitwireless communication device transmission have an identification codeand the wireless cold water control valve device and the wireless hotwater control valve device respond only to transmission bearing theidentification.
 9. The on-demand faucet system of claim 8, wherein thezone of detection is such that the sensor is capable of detectingpresence and wherein the zone of detection is movable in relation to thefaucet.
 10. The on-demand faucet system of claim 8, further comprising atemperature sensor positioned in thermal contact with the water supplyline and in wireless communication with the sensor unit, the sensor unitcomprising a display for indicating the temperature of the water. 11.The on-demand faucet system of claim 10, further comprising atemperature triggered water shut-off switch positioned on the watersupply line and in communication with the temperature sensor, whereinthe flow of water to the faucet is stopped when the temperature sensordetects a temperature above a predetermined limit.
 12. The on-demandfaucet system of claim 8, further comprising an automatic shut-offtimer, activated when the control valve device is switched from closedto open and which changes the state from open to closed after apredetermined period.
 13. The on-demand faucet system of claim 8,further comprising a manual actuator positioned on the sensor unit andin communication with the sensor unit wireless transmitter whereinactuation of the actuator initiates a transmission of a signal to one orboth of the hot and cold control valve receivers.